Stalin was the deputy chief minister of Tamil Nadu between 2009 and 2011.

DMK supremo M Karunanidhi named DMK treasurer and former Tamil Nadu Deputy Chief Minister MK Stalin as his political heir, which may cement his brother MK Alagiri's split from the party. Stalin is the third son of Karunanidhi, who is 92 years old.

Stalin first became a Tamil Nadu minister after the Assembly elections in 2006. He was the deputy chief minister from 2009 to 2011. It was speculated that if DMK had won the 2016 Assembly elections he would have become the chief minister.

He has recently been in news over leading protests, including the Rail Roko campaign over the Cauvery water dispute. His party members were also suspended from the Tamil Nadu Assembly recently for creating a ruckus in August 2016. Alagiri had sat in protest and had to be carried out by security from the Assembly house after he was suspended for a week.

He was chosen for the position of DMK chief over his brother MK Alagiri, who has been sidelined and later threatened to split from the party. Stalin has been helping his ageing father who no longer is able to manage the day-to-day affairs of the party.

Alagiri was also snubbed during the Assembly elections and did not get any responsibilities then. Alagiri had resigned from the central government position in 2013 after the DMK withdrew support to the UPA government over treatment of Tamils in Sri Lanka.